I lost my Mentor to a crash tonight, which is disappointing because it's my first crash. I wouldn't be so disappointed, but I don't know what even caused it. I'm hoping someone can shed some light.
Here's my set-up.
Futaba 6EX 2.4gHz radio set.
APM2 running 2.50
3dr 433 Telemetry
External MediaTek GPS
Lipo 4000mAh 3S
Had been flying for quite a while, and was on the last flight of the last battery. (plenty of charge left though, 11.6 volts right before I took off. Anyway, rest of the flights had gone great. I had finally gotten the PIDs dialed in so FBW-A worked flawlessly. Even ran a couple rectangular patterns in Auto. Navigation needed some tuning, but that is a different subject.
So I take off in stabilize switch to FBW and one tight climbing right turn and then a gradual climbing right turn and all of a sudden I get an uncontrollable pitch down, and since I was still climbing at a high power it shot toward the ground quite quick. Tried to switch back to stabilize mode, but I think I was too late.
Data log exists up until just before impact. Funny thing is that it shows pitch up the entire decent, when I know for a fact that it was nose down during the whole incident. Hit the ground at 28 m/s. Destroy the fuselage of the plane, but all electronics survived. Servos and APM seem to function normally after hooked the back up on the bench. APM shows correct pitch and roll.
Did my APM lock up or will I never know what happened?